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  1. #11
    i will look at that once i get the everything off. thanks guys!

  2. #12
    I just got to the carbs today. The oil lines are really tight. I had to cut the lips open to pull them. The carbs 6 nuts were not that tight. The gasket seal around the middle card was kind of loose. There was some kind of adhesive between the gasket and card around the other two carbs but the middle didn't. I don't think it was sealed correctly. Could air leak around the carbs base cause this melt down. I just put in the order for new carb rebuilt kit and will tear down when I get it. I have a feeling that the middle carb is not clogged. Gasket is really new. Maybe it was just rebuilt before the it was sold to me, about 6 months ago. If oil lines are good, carbs not clogged, could air leak cause this damage?

  3. #13
    Myself's Avatar
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    Yes, an air leak at the carb base will cause a lean condition. Pop the cast rectangular cover on that center carb. Let's see the round check discs.

  4. #14
    you mean the fuel pump diaphragm or the fuel pump side? i think it maybe running rich. the spark plugs are dark. i'll take some pics soon.

  5. #15
    Myself's Avatar
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    The pump side, 2 little round discs with a little rubber center.


  6. #16
    I opened the middle carb today. I am left with more questions than answers. The carb looked cleaned. Nothing was wrong as far as I can see. I have uploaded all the of the pictures. Can you guys see anything wrong with it. The other two carbs are very much similar to it, but less corrosion between check valves black gasket and the fuel filter, picture #6.

    If the gasket between the check valves plate and the fuel filter is compromised, picture #6, not the clear pulse pump plastic. Can it cause this piston and cylinder damage? It was also running very rich. The H and L adjustment screws were about 2 turns out.
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  7. #17
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    Hard to see the check discs with the glare but if they are still flat with no little creases anywhere they're good. Sounds likely you were sucking air around the base gasket.

  8. #18
    I know the oil lines didn't fall off, carbs are good. The High and Low adjustment screws were 2 turns out. The thing was running rich. I also see dark liquid at the bottom of the crankcase under the damaged cylinder, possibly oil and gas. The spark plugs are dark. If I was running full speed, 49mph on gps, and one of the spark plugs fouled, could this kill the piston and cylinder?

  9. #19
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    First take the primer bulb out, what made you think that pressurizing the fuel tank would help/fix your problem? Next take the piston out of the cylinder and take some pics, hard to tell what happened by looking at the top of the piston.

  10. #20
    I’m in this same position with an suv engine with a melted down cylinder and I pulled that carb to the corresponding cylinder and one of those little clear check plates has creases in it... would that cause a lean condition in the carbs?

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